A cobposation oe delays abb



T. MIDGLEY, IR. y

FUEL TANK. APPLICATION FILED JULY 5.1918.

Patented Aug. 1, 1922.

fo rn ai@ UNITED STTES )earner ortica.

, THOMAS ,MIDGLESL in., 0F DAYTON, orriojnssiewon, BY rfiEsNn .essrGfNMEN'rs To nnLoo-Lrenr, COMPANY, on DAYTON, onro, e. ooaronnrron'oii DELAWARE.

FUEL TANK. l

Patented Aug. 1, 1922.

Application filed July 5, 1918. Serial No. 243,316.

To all whom t may concern: y

Be 1t known that I, THOMAS Minennr, Jr.,

citizen of the United States of America,

residing Dayton, county of Montgomery, State of Ohio, U. S. A.,have invented certain new and useful Improvements in Fuel Tanks, of which the following is a full, clear, and exact description. v

The present invention relates to fuel suppiy systems of the type wherein the suction of the engine directly elevates the fuelV from the'fuel supply tank, located below the level of the fuel intake of the engine. In fuel supply systems of thistype fuel is drawn up from the supply tank and flows through the mixing valve wherein it is properly mixed with air also drawn in by the suction of the engine. Y

It is an objection in the usual forms of fuel supplying systems of this type, where the suction of the engine tends to draw -fuel directly from the tank, that the varying head of the fuel in the tank tendsalso to affect the ldow of fuel when brought under the effect of the engine suction. That is, when the tank is full, the suctionefi'ect of the engine will be assisted to a greater degree by the head of fuel in the supply tank than when the tank is nearly empty. This condition tends to cause the engine to be supplied with a richer mixture when the fuel` tank is full than when the tank is nearly empty; and this mixture will gradually grow lean as the tank becomes empty, when the mixturc'will be extrem ely lean, since then the suction of the engine is the` only factor effecting the "flow of the fuel to the engine.

'ihe chief object of the present invention is to provide a fuel tank wherein the effect of a varying head of fuel will be substantially eliminated, so thatthe suction of the engine tained constant while the fuel supply tank is being refilled;

Other and further objects of the present invention will'be apparent from the 'following description of a preferred embodiment tliei'eof,i-efe1'ence being had to the accompanying drawing:

The figure `of the drawing shows a cross sectional view of the fuel tank constructed in accordance with the present invention, together with. a fragmentary illustration of an engine with which' the fuel tank may used. l

i In the drawing, 2() designates the cylinder head of the internal-combustion engine having a fuelintake 2l, into which air is drawn and fuel is drawn up by the suction action of the engine vthrough the fuel pipe 22, which extends nearly to the bottom of the fuel tank 23. Fueltankl23 Ais provided with an opening` 24sfor filling, which is closed by a hinged cover 25 which tightly seats upon the flange24which surrounds the opening From the top wall of theta-nk 23 there depends a circular wall or apron 2G which extends nearlyto the bottom of the tank 23, but above the lower end of 'pipe 22. The apron' 26,'together with the portion 27 of the upper wall of the fuel tank 23, forms a conduit or chamber 28 which is openr at the bottom except when sealed by the fuel contained in the tank, and has a small vent 3() at the upper end thereof.v The space in the fuel tank surrounding chamber 28 will be known as chamber 29;

The operation of the tank is as follows:

The cover 25 is swung around on its pivot topermit pouring of fuel'into the tank through the opening 24, yafter which the opeijiing is closed by'bringing cover 25 into position upon flange 241?. lThe level of the fuel in the tank 23 and chamber 28 is indicated bythe line AA- The engine being started, fuel will be sucked up through pipe 22 by the suction action of the eng-ine. The level of the lfuel-inchamber 28 will adually drop from the line ,ffii- AV to the line B--B at Athe lower end yof Athe', said chamber and on this line 'there will' be established what maybe termed a' true hydrostatic level which will remain constant forthis device. It is from this level that the engine suction must'lift'the-fuel to the fuel intake 21, the eifective fuel head in the tank being now the (sov column of fuel below the hydrostatic level. Up to this time in the operation of the fuel supplying system, the level of the fuel in the chamber 29 will remain substantially at line fir-A, since no air can enter chamber 29, the cover 25 being firmly retained in place by atmospheric pressure or by'other means. As the engine continues further to operate, there will be a tendency for theV fuel to drop below the line BB in chamber 28, causing` circulation of air bubbles around the lower edge ofthe apron 26, and up through the fuel in the chamber 29'to the space above line A-A, the circulation of the bubbles being indicated by the arrow 31. As more fuel is drawn out of the tank 23, the levelA-A will gradually'descend, the fuel drawn out being displaced by air which enters at vent 30 and circulates down through chamber 28 and bubbles around the lower edge of apron 26. The bubbling action referred to will continue until the level 17k-' A has been lowered to the level B-B. Up to this time in the operation of the fuel system, the head of the fuel in the tank 23 between levels A-A and B-B, is balanced by the difference in pressure between atmosplieric pressure and the pressure of the air above the .level ier- A. When level A -A has reached B*B, the pressure above the level A-A will of course have increased to atmospheric pressure.

TWhile the fuel pipe 22 has herein been shown as passing down through the auxiliary chamber 28, it is to be understood that this is not essential, and that the fuel pipe may traverse through any other part of the fuel tank, and the auxiliary chamber 28 changed in its shape, proportions or location, as may be desired; also, that the fuel pipe 22 need not open into the fuel chamber 29 below the hydrostatic level B-B and immediately below the auxiliary chamber 28, as shown, but that it may open into the fuel chamber at any other point thereof below the level A-A of the fuel.

It will be apparent in the initial operation of the fuel system described, that the fuel mixture will be richer by reason of the head of fuel contained in the chamber 28 above the hydrostatic level B-B, but since the volume of chamber 28 is made very small in proportion to the chamber 29, the fuel head referred to will rapidly disappear so that during the normal operation of the engine the fuel head will be constant, and will be that represented by the difference between the level :Be-B and the bottom of the tank. In practice it is usually desirable toemploy a richer fuel mixture at the start, and in that case the presence of fuel lin chamber 28 would be an advantage rather than an objection. Y

lNhen. it is desirable that the. fuel mixture Aat the sta-rt bethe sameas that during the normal operation of the engine, the vent 30 is provided with a valve which is normally open when the lid 25 is closed, but which is automatically closed when the lid 25 is open, so that during the filling operation of ythe tank, the fuel ascends only a short distance in the chamber 28. By means of `such a device the head of fuel in chamber formed in lug 4l provided on the bracket 40, and said stem 42 carries at its lower end a valve 43k adapted to cooperate with the vent 30 to close oft the communicationbetween the auxiliary chamber 28 and the outside air. rEllis valve 43 is maintained in rihe tank 23 sup-v closed position by means of spring 44 which is confined between the lower surface of lug 4l and the upper surface of valve 43. Pivoted to the lever 44 is a hook member 45 carrying at its lower end a hook proper 46. This hook 46 is adapted to be engaged by lid 25' when the latter is swung downwardly to closed position. rIhe weight of the lid 25 is such as to effect the upward movement of the valve 43 against the compression of the spring 44, so that when the filling opening 24 of the tank 23 is closed, communication between the auxiliary chamber and the atmosphere will be automatically established. Then the lid 25 is moved upwardly, the spring 44 will be released and will effect the closingof the aperture or vent 30 by means of the valve 43.

W'hile the vform of mechanism herein shown and described constitutes a preferred form of embodiment of the invention, it is to be understood that other lforms might be adopted, all coming` within the scope of the claims which follow.

I claim :k

l. In a fuel supply tank for internal-com bustion engines, the combination with a normally sealed fuel chamber, of an auxiliary chamber located above the bottom of the fuel chamber open to atmosphere and communicating atv the bottom with the fuel chamber; and a. pipe leading to the engine intake from la level near `the bottom level n of the fuel chamber. said fuel chamber beinglocated below the level of the engine intake. 4

2. In a` fuel supply tank for internalcombustion engines, the combination with a fuel chamber provided with a normally sealed filler opening; of an auxiliary chamber within the fuel chamber and open at the lower end to communicate with the fuel chamber at a level near the bottom thereof, said auxiliary chamber being .open to the atmosphere; and a fuelsupply pipe leading to the engine intake from a level near the bottom of the fuel chamber. r

3. ln a fuel supply tank for internal-combustion engines, the combination with a fuel chamber provided with a normally sealed fillerl opening; of an auxiliary chamber formed by an apron depending from the top wall of the tank, said apron terminating above the bottom of the'fuel chamber; a vent for the auxiliary chamber; and a fuel supply pipe leading to the engine intake from a level between the lower edge of the apron and the bottom of the fuell chamber.

fl. ln a fuel supply tank for internalcombustion engines, the combination with a normally closed fuel chamber; of an auxiliary chamber within the fuel chamber, the auxiliary chamber having avent to the atmosphere and having communication with the fuel chamber whereby a hydrostatic level may be established therein; and a fuel pipel leading from the fuel chamber to the engine intake. v

5. In a fuel supply tank for internal-combustion engines, the combination with a normally closed fuel chamber; of an auxiliary chamber having a vent to the atmosphere and having communication with the fuel chamber whereby a hydrostatic level may be established therein; and a fuel pipe leading from the fuel chamber to the engine intake, the fuel chamber being located below the level of the engine intake.

6. ln a fuel supply tank for internal-combustion engines, the combination with a normally closed fuel chamber; yof an auxiliary chamber having a vent to the atmosphere and having communication with the fuel chamber whereby a hydrostatic level may be established therein; and a fuel pipe passing through the auxiliary chamber from the 4 fuel chamber to the engine intake.

7. In a fuel supply tank for internal-combustion engines, the combination with a normally closed fuel chamber; of an auxiliary chamber formed by an apron depending from a wall of the tank and having a vent to the atmosphere whereby a hydrostatic level may be established in the fuel chamber; and a fuel pipe inside the apron leading to the engine from the fuel chamber.

8. A fuel, tank comprising a normally closed fuel chamber; an auxiliary chamber having a vent to the atmosphere and communicating with the fuel chamber whereby a hydrostatic level may be established therein and means for Vclosing the vent.

9. A fuel tank comprising a normally closed fuel chamber; an auxiliary chamber having a vent to the atmosphere and communicating with the fuel chamber whereby a hydrostatic level may be established therein; and means operative upon opening the fuel chamber to the atmosphere for closing the vent. y l

l0. A fuel tank comprising a normally closed fuel chamber; an auxiliary chamber having a vent to the atmosphere and communicating with the fuel chamber whereby a hydrostatic level may be established therein; and means for closing the vent, said means beingv inoperative while the fuel chamber is closed. 1l. In a fuel supply tank for internalcombustion engines, the combination with a fuel chamber provided with a normally closed iiller opening; of an auxiliary chamber within the fuel chamber and communicating with the fuel chamber at a level near the bottom thereof, said auxiliary chamber being open to the atmosphere; and f a fuel supply pipe leading'to the engine intake from a level near the bottom of the fuel chamber; and means acting automatically when the filler opening is uncovered to close ofi' v communication between the auxiliary chamber and the atmosphere.

l2. In a fuel supply device for internalcombustion engines, the combination with a normally closed fuel tank; of va device for maintaining a constant hydrostatic level within the fuel chamber, said device includ.- ing a chamber having communication with the atmosphere and with the fuel tank; and means acting automaticallywhen the fuel tank is open to the atmosphere to close off the communication between the chamber and the atmosphere.

In testimony whereof l affix my signature. 

